Pillow



FIG. 1 is a front elevation of a pillow showing my new design;

FIG. 2 is a rear elevation thereof; and,

FIG. 3 is a side elevation as seen from the right side of FIG. 1.

The broken lines shown in FIG. 1 are for illustrative purposes only and do not form part of the claimed design. 

The ornamental design for a pillow, as shown and described. 